Aleiodes ruficornis ( Herrich-Schaeffer , 1838)

van Achterberg, Cornelis, Shaw, Mark R. & Quicke, Donald L. J., 2020, Revision of the western Palaearctic species of Aleiodes Wesmael (Hymenoptera, Braconidae, Rogadinae). Part 2: Revision of the A. apicalis group, ZooKeys 919, pp. 1-259 : 1

Aleiodes ruficornis ( Herrich-Schaeffer, 1838) Figs 667-669 , 670-681 , 682-685

Rogas ruficornis Herrich-Schäffer, 1838: 156, fig.; Shenefelt 1975: 1224 (as synonym of A. dimidiatus ) [neotype designated below].

Aleiodes (Neorhogas) ruficornis ; Papp 1985a: 152 (as synonym of A. dimidiatus ), 1991a: 90 (id.).

Aleiodes (Chelonorhogas) ruficornis ; Belokobylskij et al. 2003: 398; van Achterberg 2014: 209; Abdolalizadeh et al. 2017: 37.

Aleiodes ruficornis ; Bergamasco et al. 1995: 5; Zaldívar-Riverón et al. 2004: 234; Papp 2005: 176 (as synonym of A. dimidiatus ).

Aleiodes brevicornis Wesmael, 1838: 98; Shenefelt 1975: 1224; Papp 1985a: 152, 157 (as synonym of A. dimidiatus ), 2005: 176 (id.); Belokobylskij et al. 2003 (as synonym of A. ruficornis ) [examined].

Aleiodes (Neorhogas) brevicornis ; Papp 1991a: 90 (as synonym of A. dimidiatus ).

Aleiodes nigripalpis Wesmael, 1838: 97; Shenefelt 1975: 1224; Papp 1985a: 152, 157 (lectotype designation; as synonym of A. dimidiatus ), 1991a: 90, 2005: 176 (id.); Belokobylskij et al. 2003 (as synonym of A. ruficornis ) [examined].

Rhogas dimidiatus ab. nigrobasalis Hellén, 1927: 24 (invalid name).

Rhogas dimidiatus ab. ruficollis Hellén, 1927: 24 (invalid name).

Rhogas carbonarius ab. giraudi Fahringer, 1931: 236 [unavailable name for melanistic males].

Rhogas carbonarius var. giraudi Telenga, 1941: 168. Syn. nov.

Rogas dimidiatus ab. infuscatus Hellén, 1957: 49 (invalid name).

Rogas dimidiatus ab. nigripes Hellén, 1957: 49 (invalid name).

Aleiodes (Aleiodes) arnoldii ; Farahani et al. 2015: 232-233 (but see note under A. arnoldii ).

Rogas gasterator auctt. p.p.

Rogas dimidiatus auctt. p.p.

Type material.

Neotype of A. ruficornis here designated, ♀ (NMS), "[Germany,] Einbeck, L. 31.v.[19]85, [R. Hinz]", "ex: Hoplodrina blanda Schiff. (Lep.)". Holotype of A. brevicornis, ♀ (KBIN), " A. brevicornis ♀ mihi. 3.", "Coll. Wesmael", " A. brevicornis mihi, dét. C. Wesmael", " Belgique, Liège, leg. Robert/ teste Papp J., 1983", "Holotypus Aleiodes brevicornis Wesm., 1838 ♀, det. Papp, 1983", " Aleiodes dimidiatus Spin. ♀, det. Papp J., 1983". Holotype of A. nigripalpis , ♂ (KBIN), " A. nigripalpis ♂ mihi. 2.", "Coll. Wesmael", " A. nigripalpis mihi, dét. C. Wesmael", "Belgique, Liège / teste Papp J., 1983", "Lectotypus Aleiodes nigripalpis Wesm., 1838 ♂, det. Papp, 1983", " Aleiodes dimidiatus Spin. ♂, det. Papp J., 1983". The neotype designation for A. ruficornis is necessary for nomenclatural stability, because the types of Braconidae described by Herrich-Schäffer are lost (Horn and Kahle 1935-37; the first author could not find any specimen in ZMB) and the species has been confused with similar species in the past. The specimen is selected because it fits well the original description, the probable type location was in Germany, it has been reared and it is in good condition.

Additional material.

Andorra, Austria, British Isles (England (V.C. 5, 11, 13, 15, 17, 19, 20, 22, 23, 24, 28, 29, 31, 33, 38, 39, 60, 63); Wales (V.C. 52) [no specimens seen from Scotland]), Bulgaria, Croatia, Czech Republic, Finland, France, Germany, Greece, Hungary, Italy (including Sicily), Moldova, Montenegro, Netherlands (DR: Borger; LI: Venlo, ZH: Oostkapelle), North Macedonia, Norway, Romania, Russia (including Far East), Serbia, Slovakia, Sweden, Switzerland, Turkey, Ukraine, [Afghanistan, Dagestan, Iran, Kazakhstan, Kyrgyzstan]. Specimens in ALC, ZJUH, BZL, FMNH, MMUM, MRC, MSC, MSNV, MTMA, NMS, NRS, OUM, RMNH, SDEI, UNS, UWIM, ZISP, ZSSM. This is a widespread species, generally common, but partly replaced by A. gasterator in the Mediterranean region.

Molecular data.

MRS140 (UK), MRS877 (Sweden), MRS888 (UK), MRS890 (UK), MRS891 (UK).

Biology.

Specimens collected from April-September; probably plurivoltine in the southern part of its range but in Britain univoltine, flying from June-August with a varied means of overwintering (see below). Reared from the noctuids Agrotis clavis (Hufnagel) (4 [4 ZISP]/ Russia), Agrotis segetum (Dennis & Schiffermüller) (1 [FMNH]/Finland), Agrotis sp. (3), Euxoa nigricans (Linnaeus) (1 [FMNH]/Finland), Euxoa sp. (3:1 [3 FMNH/Finland], Hoplodrina blanda (Dennis & Schiffermüller) (4:1, Germany; R. Hinz), Hoplodrina octogenaria (Goeze) (1; W. A. Watson), Mythimna impura ( Hübner) (1 [ZSSM]/Germany; E. Haeselbarth). A further mummy from H. blanda failed to emerge (M.R. Shaw), but was no doubt of this species. The above hosts belong to three different subfamilies of Noctuidae , all feeding and resting close to ground level. In addition, we have seen a specimen labelled as ex the nymphalid Brenthis ino (Rottemburg) but accompanied by a mummy of a noctuid, probably Hoplodrina sp. (det. M.R. Shaw). In experiments a range of hosts recorded for this species in the literature (several arctiine and lymantriine Erebidae and the lasiocampid Lasiocampa quercus (Linnaeus)) that are actually hosts of superficially similar species such as A. alternator (Nees) were offered to the female reared ex H. octogenaria but, as expected, they were firmly rejected. However, this female readily accepted late 1st instar larvae of Agrotis exclamationis (Linnaeus), from which adult progeny resulted very smoothly (1:16\13\\12\12+0. The few failures to oviposit were almost certainly due to egg depletion). Searching in the vicinity of hosts included antennal drumming (the tips curled downwards) and indeed the antennae seemed to be the only proximal means of locating and assessing the host. Once the host was found it was immediately accepted, rapidly jabbed and stood over or often withdrawn from (1.0-1.5 cm) while the venom took affect (20-40 secs), then relocated via antennal searching (when it had been withdrawn from this might take up to a minute, but it was always eventually successful) scooped in with the fore legs (the antennae only slightly involved), positioned and held between the mid legs for the duration of oviposition (20-30 secs). Frequently the host larva was kicked free of the ovipositor by the parasitoid’s hind leg(s) and the parasitoid rapidly left without any period of post-oviposition association. Recovery from the venom was rather protracted (up to 20 mins), during which time hosts were rejected if rediscovered. Towards the end of successful oviposition runs it was evident that venom depletion ran ahead of egg depletion, resulting in erratic (but nevertheless successful) oviposition sequences. No host feeding took place. In this experimental series oviposition took place in mid-July with mummification at the end of August and adult emergence in late May of the following year. However, although the winter was passed in the mummy in this entire series (and probably also the case for the other, natural, Agrotis hosts), it is clear that the rearings from Hoplodrina and probably also Mythimna involved overwintering in the host larva with adult emergence in the year of mummification. This host-related difference in overwintering is not inconsistent with univoltinism in Britain (where the experiments and other observations were done) but it is certainly an interesting quirk of its host range and might be of significance in suggesting one way in which a temporal isolating mechanism could potentially arise as a forerunner to speciation (cf. Shaw, 2003). The mummy is formed in the soil and is not strongly (if at all) glued to the substrate. It is predominantly dark brown in colour, very large in relation to the size of the insect that will emerge and, although basically cylindrical, somewhat flattened in appearance owing to a pronounced but blunt lateral keel (Fig. 669 ). It is more or less strongly contracted at the anterior end, markedly less so caudally, and the copiously silken lining typically occupies 3rd-8th abdominal segments.

Diagnosis.

Maximum width of hypoclypeal depression 0.4-0.5 × minimum width of face (Fig. 676 ); OOL of ♀ 1.4-1.6 × as long as diameter of posterior ocellus and distinctly rugose or rugulose (Fig. 677 ); length of 4th antennal segment of ♀ 1.0-1.4 (of ♂ 1.1-1.4) × its width (Fig. 679 ); ventral margin of clypeus thick and not protruding anteriorly (Fig. 678 ); lobes of mesoscutum densely punctate, interspaces largely smooth and shiny; precoxal area coarsely vermiculate-rugose medially; marginal cell of fore wing of ♀ usually ending rather removed from wing apex (Fig. 670 ); vein 1-CU1 of fore wing 0.4-0.6 × as long as vein 2-CU1; hind tarsal claws yellowish or brownish bristly setose and with few yellowish pectinal teeth (Fig. 681 ); hind femur at least apico-dorsally dark brown or black; inner side of hind tibia of ♀ yellowish; pale males have whole frons and stemmaticum yellowish; palpi dark brown or blackish, rarely brown; 3rd metasomal tergite only antero-laterally reddish or yellowish; 4th and 5th tergites black. Specimens from high altitude have the head conspicuously long setose and the tarsal claws brownish pectinate basally. In this respect males are similar to A. hirtus , but A. hirtus has precoxal area and mesoscutum largely smooth and clypeus distinctly protruding in lateral view.

Description.

Neotype, ♀, length of fore wing 3.9 mm, of body 6.5 mm.

Head. Antennal segments of ♀ 35, antenna as long as fore wing, its subbasal and subapical segments robust (Figs 679 , 680 ); frons with curved rugae; OOL 1.2 × diameter of posterior ocellus, rugose and moderately shiny; vertex rugose, rather shiny; clypeus rugose; ventral margin of clypeus thick and not protruding forwards (Fig. 678 ); width of hypoclypeal depression 0.5 × minimum width of face (Fig. 676 ); length of eye twice temple in dorsal view (Fig. 677 ); vertex behind stemmaticum rugose; clypeus below lower level of eyes; length of malar space 0.5 × length of eye in lateral view; temple punctate and shiny, but rugulose near occipital carina.

Mesosoma. Mesoscutal lobes distinctly punctate, interspaces of lateral lobes smooth and shiny; precoxal area of mesopleuron coarsely vermiculate-rugose medially, but posteriorly punctate; mesopleuron punctate medially; metapleuron distinctly rugose ventrally and dorsally punctate; scutellum largely smooth (except for punctulation), rather shiny and nearly flat, with lateral carina; propodeum coarsely reticulate-rugose, laterally dorsal face longer than posterior one, somewhat angulate laterally but without tubercles, and with complete medio-longitudinal carina.

Wings. Fore wing: r 0.3 × 3-SR; marginal cell short (Fig. 670 ); 1-CU1 horizontal, 0.5 × 2-CU1; r-m 0.6 × 3-SR; 2nd submarginal cell medium-sized (Fig. 670 ); cu-a inclivous, straight; 1-M rather curved posteriorly; 1-SR slightly wider than 1-M; surroundings of M+CU1, 1-M and 1-CU1 largely setose. Hind wing: marginal cell linearly widened, its apical width 2.2 × width at level of hamuli (Fig. 670 ); 2-SC+R subquadrate; m-cu narrowly pigmented; M+CU:1-M = 30:19; 1r-m 0.6 × 1-M.

Legs. Tarsal claws mainly setose and medially with 4 yellowish rather short pectinal teeth (Fig. 681 ); hind coxa punctate and shiny; hind trochantellus robust; length of hind femur and basitarsus 3.3 and 4.0 × their width, respectively; length of inner hind spur 0.5 × hind basitarsus.

Metasoma. First tergite rather convex medially, 0.9 × longer than wide apically, robust and coarsely irregularly longitudinally rugose as 2nd tergite; 1st tergite and basal half of 2nd tergite with medio-longitudinal carina; medio-basal area of 2nd tergite triangular and rather distinct (Fig. 673 ); 2nd suture deep and crenulate; basal half of 3rd tergite largely longitudinally striate, remainder of metasoma superficially micro-sculptured or smooth; 4th and apical half of 3rd tergite without sharp lateral crease; ovipositor sheath wide, with medium-sized setae and apically truncate (Fig. 668 ).

Colour. Reddish or orange-brown; stemmaticum medially, malar space largely, temple and occiput ventrally, mesosternum, mesopleuron ventrally, 3rd tergite (except antero-laterally), 4th-7th tergites black; palpi (only labial palp darkened basally) brown; basal half of antenna, tegulae, parastigma, and base of pterostigma pale yellowish; apical half of antenna, pedicellus dorsally, propodeum dorsally and medially, middle and hind femora apico-dorsally, and telotarsi dark brown; remainder of pterostigma and veins dark brown or brown (Fig. 670 ); fore wing membrane rather infuscate, but hind wing nearly subhyaline.

Variation. Female: mesosoma occasionally wholly black. Male face and mesosoma usually black but can be variably marked with red; scape and pedicel usually (partly) reddish in central and southern populations but most often entirely black in more north-western ones (e.g., British Isles, Sweden); hind coxa varies from black to red. Length of malar space 0.5-0.6 × length of eye in lateral view; head black or largely reddish brown (except temple ventrally and malar space); interspaces of mesoscutal lobes smooth to micro-sculptured; 1-CU1 0.4-0.6 × 2-CU1; 3rd tergite longitudinally striate or rugulose basally (sometimes narrowly so), without curved sculptural elements (Fig. 673 ), except sometimes some weak transverse striae occasionally present at extreme apex; males from montane habitats are generally darker than lowland males. Antennal segments: ♀ 34(6), 35(12), 36(15), 37(22), 38(17), 39(13), 40(2), 41(3), 42(2), 43(1); ♂ 43(1), 44(1), 45(1), 46(1), 47(5), 48(13), 49(32), 50(19), 51(36), 52(36), 53(28), 54(11), 55(4), 56(4), 57(2). On average males have ca 14 more antennal segments than females. Male has marginal cell of fore wing less robust than in ♀, with apical tergites type 1-2, density of setae rather variable and fringe evident but sparse (Fig. 682 ).

Distribution.

*Afghanistan, *Andorra, Austria, British Isles (England, Wales), *Bulgaria, *Croatia, *Czech Republic, *Finland, *France, Germany, *Iran, *Kazakhstan, *Kyrgyzstan, *Montenegro, *Netherlands, *North Macedonia, *Norway, *Romania, *Russia (including Dagestan and Far East), *Serbia, *Slovakia, *Sweden, Switzerland, *Turkey, *Ukraine.

Notes.

An examined female (NMS) from Hungary, Borzsony Mts., 140 m altitude, 20-30.vii.2005 (unfortunately, too damaged for description) represents a very similar but new species. The 4th-10th antennal segments are not moniliform, slenderer than in typical A. ruficornis , the fore femur is more robust than in A. ruficornis , and the COI sequence (MRS886) is different (2.1 %).

Aleiodes ruficornis is the commonest and most widespread of a small group of related species parasitising grassland and “cutworm” hosts, exhibiting strong sexual dimorphism with unremarkable males but the more extensively orange females having a stronger build and much shorter antennae. The least extreme in these respects is A. gasterator , which largely (but not completely) replaces A. ruficornis in the Mediterranean region. Aleiodes grassator is similar to A. ruficornis , but it appears to be restricted to montane and northern habitats where it might be thought to replace A. ruficornis . However, some males that morphologically agree best with A. ruficornis have been collected at high altitude in the Alps (up to 2550 m), where A. improvisus also occurs, but whether these high-altitude A. ruficornis males are parts of breeding populations or have simply been carried up in thermals is impossible to say. The females in this group (excluding A. gasterator ) are scarcer in collections than males, as they fly very little and rarely enter Malaise traps.

Figures

Figures 667 - 669. Aleiodes ruficornis (Herrich-Schaeffer), ♀, neotype 667 habitus lateral 668 ovipositor sheath lateral 669 mummy of Hoplodrina blanda (Denis & Schiffermueller).

Figures 670 - 681. Aleiodes ruficornis (Herrich-Schaeffer), ♀, neotype 670 wings 671 mesosoma lateral 672 mesosoma dorsal 673 metasoma dorsal 674 fore femur lateral 675 hind femur lateral 676 head anterior 677 head dorsal 678 head lateral 679 base of antenna 680 apex of antenna 681 outer hind tarsal claw.

Figures 682 - 685. Aleiodes ruficornis (Herrich-Schaeffer), ♂, U. K. (culture) 682 habitus lateral 683 apex of antenna 684 base of antenna 685 mummy of Hoplodrina octogenaria (Goeze).